This renewal proposal requests partial support for the 2005, 2007 and 2009 meetings of the Federation of American Societies of Experimental Biology (FASEB) Summer Conference on 'Autoimmunity'which is normally held every other June at the Vermont Academy in Saxtons River, VT. Historically, this meeting has been fully subscribed attracting approximately 200 registrants (the upper limit accommodated at the Vermont venue) and alternates years with the FASEB Summer Conference on 'Lymphocytes and Antibodies'. The purpose of the conference is to bring together basic top immunologists and clinical researchers from academia and the pharmaceutical industry at the professorial, post-doctoral and pre-doctoral levels from around the world to share the latest advancements in understanding of the pathogenesis and regulation of autoimmune disease. Autoimmune diseases together affect approximately 5% of the population targeting every major organ system and thus represent a significant health problem. However, there is not yet clear understanding of their etiologies and at present there are no cures and few useful therapies. The goal of this meeting is to merge data from animal models and patient studies on a broad range of autoimmune diseases;to share recent advances on the development of the T cell and B cell repertoires;mechanisms underlying the establishment and loss of self tolerance;the contribution of genetic and environmental (infectious) triggers to autoimmune disease development and progression;trafficking of autoreactive T cells to sites of inflammation;the pathogenetic mechanisms involved in tissue injury;and the latest therapeutic strategies for regulating autoimmune diseases. A major strength of the meeting is the informal forum that brings students and fellows together with established investigators who are international leaders in this highly disease-relevant and continually growing field. In addition to the oral presentations of the invited speakers and poster presentations by other attendees, the format of the meeting allows two short talks (15 minutes in length), selected from among the submitted abstracts, to be interspersed into each of the eight sessions providing the opportunity for more formalized oral participation by selected graduate student and postdoctoral trainees. A major goal is to foster the initiation and strengthening of collaborations among scientists in the field. This conference serves as the definitive meeting for bringing together basic and clinical scientists with research interests focusing on the etiology and reaulation of autoimmune diseases.